Biasing mechanism for silent toggle action switch



y 3, 1965 v. 1.. CARISSlMl ETAL 3,194,929

BIASING MECHANISM FOR SILENT TOGGLE ACTION SWITCH Original Filed Jan.28, 1955 2 ts-Sheet 1 Fig. I.

9 as so 7 l5 5 5 9a :4 so a 52 :2 29' 26 3 1 72 6 7 8 l4 64 L 4 5e 62 5e24 J 24 4 76 86 4 g a re 42 Fig. 2.

9o I00 98 I9 90 ea 2 92 ,le 9 94 I ,BJR Z5 94 9 Lo 2| 2' IO 96 a 2 aWITNESSES INVENTORS W Vincent L. Corissimi WJ a Owen 1.. Toy! gw F M BY1-)? ATTOR EY July 13, 1965 v. L. CARISSIMI ETAL 3,

BIASING MECHANISM FOR SILENT TOGGLE ACTION SWITCH 2 Sheets-Sheet 2Original Filed Jan. 28, 1955 Fig.3.

United States Patent 3,194,925 EIASENG MECHANHSM FOR SILENT TGGGFLEACTHQN SWITCH Vincent Qarissirni, Fairiieh @onn, and Owen L. Tayior,Riansfreid, @hio, assignors to Westinghouse Eiectric orporation,Pittsburgh, Pa., a corporation of Pennsylvania Application Dec. 23,1958, Ser. No. 782,588, which is a continuation of application den. No.484,811, lien. 28, M55. Divided and this application Mar. 16, 19764,her. No. 352,162

4 Claims, (Ci. Nil -153) This application is a division of our earlierfiled application entitled Wire Device and Wire Engagement MeansTherefor, Serial No. 782,588, and filed on December 23, 1958, and thelatter application in turn was a continuation of our now abandonedapplication entitled Wiring Device, Serial No. 484,811, and filedJanuary 28, 1955.

Our invention relates to a new and improved wiring device and, moreparticularly, to a new and improved electric switch having novelfeatures of construction, whereby the switch may be produced at a lowcost.

As can readily be appreciated in marketing switches for use in lowvoltage circuits, such as the ordinary household circuit, the price ofthe device and its adaptability for the service are importantconsiderations with the purchaser. In View of these considerations, wehave designed a new and improved switch which incorporates severaldesirable service features, yet which can be produced at a low cost. Oneimportant consideration is the noise level of the switch during theswitching operation. Some prior devices have been constructed tominimize or eliminate such noise by using a switch handle mounted in aresilient material such as rubber, or have resorted to using globules ofliquid conducting material such as mercury. Each of these types ofswitches has entailed additional expense to eliminate the switch noise.

Accordingly, one object of our invention is to provide a new andimproved wiring device of simplified construct-ion.

Another object of our invention is to provide a new and improved wiringdevice which may be produced at a low cost and which incorporatesvarious desirable features.

Another object of our invention is to provide a new and improved wiringdevice having a pivotally supported operating handle slidable over awire.

A more specific object of our invention is to provide a new and improvedwiring device which utilizes a spring wire for biasing an operatinghandle in order to obtain a silent toggle action.

These and other objects of our invention will become more apparent whentaken in conjunction with the following drawings and detaileddescription of a preferred embodiment thereof, in which:

FIGURE 1 is a longitudinal cross-sectional view of a Wiring deviceconstructed in accordance with the principles of our invention taken ona plane displaced to one side of the longitudinal center line of thedevice as shown by the line II in FIG. 4;

FIG. 2 is a longitudinal cross-sectional view of the wiring device shownin FIG. 1 taken substantially on the longitudinal center line thereof;

FIG. 3 is a top plan view of the base of the wiring device as shown inFTG. l;

' FIG. 4 is a lateral cross-sectional view of the wiring device shown inFIG. 1 taken substantially along the line IV-IV thereof;

FIG. 5 is a perspective view of one terminal used in the device of FIG.1; and

BdhdfiZ Patented July 13, 1965 FIG. 6 is an exploded perspective view ofthe screwless terminals and wire clamps utilized in the wiring deviceshown in FIG. 1.

As shown in FIGURES 1 to 4 a switch constructed in accordance with theprinciples of our invention has a formed dish-shaped housing 2, which isfabricated from any suitable insulating material, such as molded plasticmaterial, which may readily be constructed with the various structuralcomponents as hereinafter described. The housing 2 comprises anapproximately rectangular base 4 having a pair of upwardly extendingside walls 6 at its outer side edges which are joined together byupwardly extending end walls 8 at each end of the base 4. A pair oflongitudinally extending spaced barriers 16 are provided on thelongitudinal center line of the housing 2 which are formed integral withthe base 4 and one of the end walls 8 of the housing 2, so as to dividethe housing 2 into two longitudinally extending chambers 3 and 3 onopposite sides of the barriers 10. In the switch shown, only the chamber3 is utilized for receiving switching means, however, as will becomeapparent from the following description, if desired, the chamber 3'could also be utilized for locating switching means therein.

Referring to FIGS. 5 and 6, the switching means located in the chamber 3includes a generally L-shaped stationary terminal 13 having an elongatedupwardly extending leg 18 with a short arm 2% extending transverselytherefrom at its upper end. A stationary switch contact 22, which may beformed from any suitable non-arcing contact material, such as a silveralloy contact material, is secured to the undersurface of the arm 20 byany suitable means, such as by being brazed or welded thereto. Althoughthe contact 22 may be of various forms, a circular form is preferable inthat it may be easily fabricated from commercially available alloy wire,whereby the switching advantages of such a metal can be obtained atrelatively low cost, and whereby special forming operations of thecontact 22 are eliminated. The leg 18 of the terminal 12 is alsoprovided with a central, vertically extending approximately halfcircular formed guide channel 24 which extends outwardly from the leg 18in a direction opposite to the leg 23 and which is transversely enlargedat its upper end. It will be noted that the upper edge of the wire guide24 is located a substantial distance below the arm 28 whereby theportion of the leg 18 between the wire guide 24 and the arm 29 may beformed into a projection 26 which extends angularly downward below theunder surface of the arm 20 and outwardly from the leg 18. The loweredge of the leg 18 is provided with a pair of integral downwardlyextending spaced tabs 28 on each side of the wire guide 24 for securingthe terminal 12 within the housing 2, as hereinafter described.

Returning again to chamber 3, the inner surface of each end wall 8 isprovided with a vertically elongated, lon gitudinally extending recess32 which is formed to receive the guide 24- therein. A verticallyelongated notch 34 is also provided in the barriers 1t and the sidewalls 6 at each side of each offset 32 which extends transversely to therecess 32 so as to form a pair of opposed notches for supporting thesides of the leg 18 of the terminal 12 adjacent each side of the guide24. The notches 34 terminate at their lowermost edges into a recessedopening 42 in the base 4 which is provided with transversely opposedoutwardly extending sloping surfaces 44. It Will thus be apparent thatthe terminal 12 may easily be located within the housing 2 by beinglocated in alignment with the recess 32 and the notches 34 and thensliding the terminal 12; downwardly therein until the lower edge of thebase 4 and the legs 28 thereof extend through the opening 42.Thereafter, in order to secure terminal 12 to housing 2 the legs 28 areforced outwardly into engagement with the outwardly sloping surfaces 44of housing 2 by any suitable deforning process.

Referring again to FIG. 6, it will be noted that the terminal 12 iscooperable with another terminal 14 which has an upwardly extending leg16 which is'formed in' with a long transversely extending formed arm 46which,

when the terminals 12 and 14 are properlylocated within the housing 2,extends below the arm 2d of the terminal 12. As shown, one end of thearm 46 is integrally joined to the upper end of the leg 16 by means ofan extension 48 which extends downwardly and angularly away from theupper edge of the leg 16, while the other end of the arm 46 is providedwith a longitudinally extending fiat portion for carrying a contact 52thereon. The contact 52 is identical to the contact 22 previouslydescribed; however, it is secured to the fiat portion 55; of the arm 46so that it is at substantially right angles to the contact 22 on the arm29. In order to control the engagement of contact 52 with contact 22 thecentral portion of the arm 4-6 is provided with an upwardly extendingportion 54, for purposes more completely described hereinafter. As theterminals 12 and .14 are current carrying members they are formed from asuitable electrical conducting material, such as a phosphorbronze alloy,which may also be readily formed and utilized as indicated.

As also shown in REG. 6 a pair of separate identical wire clamps 56 areprovided which are cooperable with the terminals 12 and 14 as more fullydescribed hereinafter. suitable material having suflicient resiliency,such as spring steel, and preferably having a hardness greater than thatof conducting wires adapted to be connected to this device, and ifdesired may be provided with a The wire clamps 5'6 may be made from any7 suitable corrosion resistant surface, such as a cadmium platedsurface. The wire clamps 56 comprise a pair of spaced extending arms 58and 60 which are joined together at one or" their ends by means of abight portion 62, whereby the arms 58 and 65) in conjunction with thebight portion 62 form a generally U-shaped portion.

The free end 64 of the arm 58 is bent angularly upward ly toward the arm60. It will be noted that the upper arm as of the wire clamp se issloped slightly upwardly and away from the arm 58 so that the free endof arm 6%) is spaced further from the arm 58 than at the bight portion62. The outer end of the arm 66 is provided with a vertically extendingportion 66 having a transversely extending integral tab 68 for securingpurposes at each of its sides. Further, the upper edge of the verticallyextending portion 66 is provided with an outwardly substantiallyhorizontal extending projection "ill having its free edge substantiallyin vertical alignment with the free edge of the projection 64.

Referring to FIGS. 1 and 3, it will be noted that housing 2 is providedwith an upwardly extending barrier 72 on substantially the lateralcenter line of the chamber 3 and that each barrier 1th is provided witha vertically extending slot '73 which is open at its top end towards thechamber 3 and .which extends downwardly from the upper edge of thebarrier til. Thus the wire clamps 5s may easily be located within thechamber 3 by merely being inserted from the open side of the housing 2so that a clamp 56 is located at each side of the barrier 72, asdescribed hereinafter. I

In order that the terminals 12 and 14 are readily electricallyaccessible from the outside of the housing 2, a pair of substantiallylongitudinally aligned semi-circu- 'lar openings 76 are provided in base4 of housing 2 which are joined to openings 42, respectively, so thatthe flat sides of the semi-circular openings 76 are substantially in alinment with the opposed inner surface of the terminals 12 and 14. Theside wall 6 of the housing 2 adjacent each opening 76 is provided withan inwardly and downwardly sloping portion '73 which joins the base 4 ata point spaced from the barrier 16? so as to form a slot St inconjunction with the adjacent side of the barrier it? of a size to guideand receive the free end of arm 58 therein. Similarly, the same sidewall 6 at each side of the barrier 72 is provided with a sloping portion82 which forms a slot 84 for guiding and receiving the bight portion 62and the adjacent portion of the arm 5-3 therein. Further, in order topermit the arms 53 to be deflected, as desired, a pair of longitudinallyspaced openings are provided between the openings 76 so as to beadjacent to the arms 53, respectively.

By this construction the wire clamps 56 and the terminals 12 and ild'mayquickly and easily be separately inserted into the housing 2 so as toform a screwless terminal arrangement. Inasmuch as the arm of theterminal 14 extends longitudinally inwardly above the wire clamps 56, itis obvious that in assembling such a s vitc'n the wire clamps 56111.netinitially be placed within the housing 2. in so inserting the wireclamps 56 within housing 2, it will be noted that the bight portions 62thereof engage the opposed vertically extending surfaces on the barrier72 so as to support the wire clamps 56 against longitudinal displacementinwardly of the chamher 3', and so that the arms and (iii of each clamp5e extend in longitudinally opposite directions. When so inserted thearm or" each wire clamp is located within its cooperable slots $6 and84, so that the ends as extend upwardly adjacent the wire guide 24 ofthe adjacent terminal 12 or 14, and are located immediately above theopenings '76 in the base 4 of housing 2, respectively. It will also benoted that the tabs which extend toward barriers lit are located withinthe slots 73 in the adjacent barrier 10, so as to locate and secure theupper arm 6b of the Wire clamp 56 and prevent the clamp 5s from rotatingwithin the housing 2 about an axis transverse to the side walls 6.Thereafter, the terminals 12 and 14 may be located as has beenpreviously described. As shown the arm 46 of the terminal 16 extendsbelow the arm 2% of terminal 12 and, accordingly, the terminal 14 isinserted from the open side of housing 2 prior to the insertion ofterminal 12. The terminal 1 is also constructed of a suitable material,such as has been indicated, having sufiicient resiliency so that the arm4-6 thereof is normally biased upwardly, whereby the contact 52 normallyengages the contact 22. When the terminals 12 and 14 are so inserted,the projection 26 thereof engages the upper surface of the projection 7bof its respective cooperable wire clamps 56, so as to bias the upper arm6%) of the wire clamp 56 downward toward the lower arm 58 thereof. Suchan arrangement prevents the wire clamps 56 from being upwardly displacedwith relation to the terminals 12 and 14 when a conductor is inserted,as hereinafter described.

When terminals 12 and 14 and wire clamps have been so assembledelectrical connections may quickly and easily be made thereto byinserting a bare electrical con ductor through either of the openings inthe base 4 of the housing 2 so that the conductor enters the lowerportion of the wire guide 24 of either of the terminals l2, and

Thereafter, additional upward force exerted on the conductor will causethe conductor to force the projection 64 of the adjacent wire clamp 56slightly upwardly so that the conductor may be forced upwardly withinthe ,wire guide 24. When the wire clamp 56 is thus deflected, aresulting force is exerted by the Wire clamp 56 upon the insertedconductor by the resilient arm 58 thereof, which provides a contactpressure between the conductor and the terminal 12 or 14 which isadequate to ensure proper electrical contact. When a force in theopposite direction is applied in attempting to remove the wire from thedevice an increasing force between the conductor and the wire clamp 56results which causes the upper sharp edge of the projection 64 of thewire clamp 56 to bite into the softer electrical conductor and toprevent the conductor from being withdrawn. The greater the forceapplied to the wire, the greater the biting force of the projection 64on the wire. The relative deflection of the clamps 56 with respect tothe terminals 12 and 14 makes it possible to obtain such holding andgripping action on various sizes of electrical conductors withoutbending the arms 58- of the Wire clamps 56 to a point where permanentset will occur. It will, of course, be obvious that the size of theopening 76 will limit the maximum size of the electrical conductor whichcan be inserted therethough, whereby the maximum deflection of the wireclamps 56 can be determined. In order to release an inserted conductor,any suitable instrument such as a screw driver or a nail may be insertedin the adjacent release slot 86 in the base 4 of the housing 2, to pushagainst the underside of the arm 58 of the wire clamp 56. Such actionwill deflect the arm 58 so that the gripping edge of the projection $4is no longer in contact with the wire, and the wire is thus free to beremoved. In addition, the configuration of the wire clamp 56 provides astop on itself which prevents the wire clamps from being over-stressedupon releasing the wire. Thus, it will be noted that the lower edgebetween the arm 60 and the portion 66 will be engaged by the projection64 of the arm 58 so as to limit the u ward deflection of the arm 58. Byproper design of the location of the clamp 56, the distance the arm 58may readily deflect can be limited so that over-stressing of the arm 58of the clamps 56 may be prevented.

As shown the open top of the housing 2 is adapted to be completelyclosed by means of a yoke 88. The yoke 88 may be fabricated from anysuitable material having sufficient structural strength, such as sheetsteel, and is provided with an arm 90 at each of its ends which extendlongitudinally outward of the housing 2. The arms 99 are provided withsuitable means, such as punched out threaded openings 92, for securingthe switch assembly .to suitable supporting means, such as an outletbox. The

yoke 88 is also provided at each end with a pair of downwardly extendingfastening lugs 94 which engage the outer surface of the side walls 6.The lugs 94 are bendable laterally into engagement with laterallyextending shoulders at opposite sides of the formed opening 96 which isformed in each end of the housing 2, whereby the yoke 55$ is secured tothe housing 2. For a more complete description of the lugs 94 andopening 96, reference may be made herein to US. Patent 2,881,279, filedby O. L. Taylor on April 12, 1954, entitled Wiring Device, and assignedto the same assignee as this invention.

If desired, in order to provide electrical insulation between the yoke88 and the terminals 12 and 14, a suitable insulator plate 93 may beprovided between the yoke 88 and the housing 2 above the contacts 22 and52. Further, if desired, the upper edges of the side walls 6 and theadjacent end wall 8 may be recessed inwardly to receive the insulatorplate 98. The insulator plate 98 may be formed from any suitableinsulating material such as a phenolic sheet. The yoke 88 is alsoprovided with a longitudinally extending elongated rectangular opening100, having its center in substantially the longitudinal and lateralcenter lines of the yoke 88, for receiving an operating member 40. Theyoke 88 is further provided with an integral upwardly extendingsemi-circular pivot guide portion 5 at each side thereof having theircenters on the lateral center line of the yoke 88 for pivotallysupporting the operating member 40.

The operating member 40 is irregular in form and is preferablyfabricated from a suitable insulating material, such as a molded plasticmaterial, which may readily be formed as hereinafter described. As shownin FIGS. 1

and 2 the operating member 46 comprises an elongated main body portion 7which is adapted to be located within the opening 100 of the yoke 83.The body portion 7 is provided with integrally formed supports 9 at eachof its sides which extend laterally outwardly therefrom and are providedwith circularly formed ends 11. The supports 9 are substantially ofequal length and each extends a distance so as to be engageable with theadjacent side wall 6. As shown in FIG. 3, each side wall 6 is providedwith a central semi-circular recess 23 which is inwardly open towardchambers 3 and 3 for receiving the lower half of the outer end 11 of itscooperating support 9. In-

asmuch as the recesses 23 support only the lower half of the ends 11,the upper halves thereof extend upwardly above the side walls 6 of thehousing 2. As previously described, the yoke 88 is provided with pivotguide portions 5 which receive the upper portion of the supports 9.Thus, when the outer ends 11 of the supports 9 are located in therecesses 23 and the yoke 88 thereafter is secured to the housing 2, theoperating member 40 is pivotally supported by its outer ends 11. Ifdesired the entire upper surface 13 of each support 9 may be providedwith the same curvature as the outer ends 11 so as to be guided by theinner surface of the guide portions 5 when the operating member 4% isrotated. It will be realized that only the outer ends 11 of the supports9 are necessary to pivotally support the operating member 40 and that,if desired, the engaging portion of the surface 13 of the supports 9 andthe guide portions 5 between the body portion 7 and each end 11 may beeliminated.

As shown in FIG. 2, each end wall 3 of the housing 2 is provided with acentral open-sided slot 19 which extends downwardly from the uppersurface thereof so as to form a pair of longitudinally opposed slots onsubstantially the longitudinal center line of the housing 2. A spring30, which may be of any suitable material having suflicient resilienc,such as spring steel, and which is preferably circular in cross section,is insertable from the top of the housing 2 so that it extendslongitudinally between the slots 19 and so that its ends are supportedby the bottoms thereof, respectively.

It will be noted that the lower part of the body portion 7 of theoperating member 4%, which projects inwardly of the housing 2 toward thespring 351, is formed in a longitudinally extending broad V-shape,having a generally V-shaped central longitudinally extending,substantially semi-circular cross-sectioned groove 17 therein. In orderto obtain a toggle action for the operating member 40, the groove 17 islocated on the body portion 7 so that when the operating member 40 is ateither of its extreme positions, spring 30 lies in one of the arms ofthe V-shaped groove 17. As hereinafter described, the spring 39 isslidably cooperable with the bottom surface of each arm of the groove17, and accordingly, the spring 30 and the groove 17 are provided withcooperable cross sections, such as the circular and semi-circular crosssections, respectively, previously described. If desired, othercooperable cross sections could be employed without affecting theoperation of the spring 3% and the groove 17.

As the spring 30 is located in one arm of the groove 17 at the right asviewed in FIG. 2, it will be noted that movement of the operating member41 from this extreme position counterclockwise towards the other extremeposition at the left will cause the apex 21 of the groove 17 betweeneach of its arms to engage the central portion of the spring 30 anddeflect it downwardly and thus stress the spring 39. The apex 21, ofcourse, comprises the junction between the bottom surfaces of the armsof the axis of the operating member 46, and the line of action of thespring force is vertically upward and extends through the pivot axis ofthe operating member 40. Further counterclockwise movement of theoperating member causes thespring 30 to enter the other arm of thegroove 17 in that this line of action of the spring force moves to theright of the pivot axis. When the spring force action is so moved to theright of the pivot axis, it will assist counterclockwise movement of theoperating member it? until the operating member 49 is in itsotherextreme position. As can be appreciated, it is desirable that theoperating member 46 be constructed so that it cannot be stopped at itsdead center position. Accordingly, the apex 21 is pointed so that theoperating member 4d is unstable when the spring force passes verticallythrough the apex 21 and the pivot axis.

The movement of the apex 21 over the spring 30' will be primarilyprovided with a rounded contour. It will also he noted that when thespring 30 engages the upper surface of one .arm of the groove 17 ateither extreme position, it is slightly deflected to bias the oper atingmember 46 upwardly into engagement with the yoke 38 at all times andhold the operating member 4% at such extreme position. It will be notedthat the bottom surface of each arm of groove 17 is slightly curvedupwardly toward its end of body portion '7 on a radius larger than thatof each point on the bottom surface of the groove 17 to the pivot pointof the operating member :9, i.e., the ends 11 thereof. ()bviously, thecenter of the circle which defines the curvature of the arms of thegroove 17 is not located on the line defined by the pivot point of thebody member 4% and the apex 21. By such construction, as the operatingmember moves past the dead center point of the spring 33, the other armof the groove 17 progressively engages the spring along the curvature ofthe arm. Such construction provides, in

etfect, a resilient stop to gradually decelerate the operating member49, and since at either end of its movement there is no suddenengagement of the spring with the groove 17, the operation of theswitch'is quiet.

As is customary, an integral handle portion 1 is provided which extendsupwardly from the main body 7 of the operating member for pivotallymoving the body portion '7 from one extreme position to another. Ifdesired, markings 25 may be located on the upper surfaces of the bodyportion '27 adjacent the handle portion 1 to indicate the position ofthe switch contacts 52 and 22 with respect to each other. Further, thebody portion 7, adjacent the outer end of each arm of the groove 17 ateach side thereof, may be provided with a downwardly extendingprojection 27 to provide an overtravel stop in conjunction with upwardlyextending stops 29 on the inner end of each barrier it Thus, anyexcessive force applied to the operating member 40 in either direc- I Asshown in FIG. 4, the portion of each support 9 between its end 11 andthe body portion 7 is provided with an integral cam which projectsdownwardly into chambers and 3 of housing 2. If no switch components arelocated in chamber 3', the cam 15 on such side of body portion '7 may beeliminated; however, it will be appreciated by so providing both cams 15a single operating member 4% may be utilized for both single and doublepole types of switch construction (reversible handle). The lower surfaceof each cam 15 is located and formed so that when the operating member40 is pivotally rotated in a counterclockwise direction, with referenceto FIG. 1, the lower edge of the cam 15 engages the upper side of theprojection 54 on the arm 46 of the terminal 14, whereby the arm 46 isforced downwardly rorn the arm 2t of the terminal 12, and the contacts52 and 2.7 are separated. In order to retain the projection 54 in thedepressed or off position, the cam 15 is provided at its inner end withan extended surface 31 which engages the projection 54- at all timesthat the cam 15 is so rotated counterclockwise. Conversely, in order toestablish contact between the contacts 52 and 22, the operating member40 is pivotally moved by the handle 1 in a clockwise direction, wherebythe surface 31 of the cam 15 is moved away from the projection 54 andthe resiliency of the arm to causes the contact 52 to move upwardly intoengagement with the contact 22;

By this construction it will be noted that we have primarily provided aswitch which is quiet in operation and which may easily be constructedby merely inserting various component parts thereof from the open sideof the housing, which parts do not require any separate means forsecuring them together or to the housing 2. Further, the means forproperly locating the component parts'of the switch within the housing2, such as the slots 15, the notches 34, the barrier 72, etc., may allbe easily provided during molding of the casing. As the contacts 22 and52 are crossed, the alignment thereof is not critical within a widerange of spacings of the ends 8 of the housing 2, and they haveessentially point contact when engaged. Also, the terminals 12 and 14,the yoke 88 and the wire clamps 56 are all of a form which are suitedfor forming by simple manufacturing processes. a

1 Having described a preferred embodiment in accordance With the patentstatutes, it is desired that the invention be not limited to thespecific construction shown and described inasmuch as it is apparentthat modifications thereof may be made without departing from the broadspirit and scope of our invention. Accordingly, it is desired that theinvention be interpreted a broadly as possible and that it-be limitedonly as required by prior art;

We claim as our invention:

1. An electric switch comprising, a rectangular cupshaped insulatinghousing, an elongated spring located within said housing and extendingtransversely between one pair of opposed walls of said housing, means ineach of said one pair of opposed walls for supporting opposed ends ofsaid spring, a body member pivotally supported above said spring by theother pair of opposed walls of said housing, said body member includinga lower surface having a central apex with an inclined surface at eachside of said apex, said spring and said body member being located withrespect to each other in said housing so thatwhen one of said inclinedsurfaces engages said spring said spring is stressed, said body memberbeing pivotally movable so that said apex further stresses said springand causes said spring to engage the other of said inclined surfaces inthe same manner, each .of said inclined surfaces being formed to curveupwardly away from said apex in a transverse direction with respectthereto on a radius longer than the distance of each point on said lowersurface from the pivot point of said body member so that progressiveengagement of each of said inclined surfaces with said spring providesresilient stopping action for said body member, separable electricalcontact means located within said housing and means on said body memberfor moving said contacts into and out of electrical engagement inresponse to said pivotal movement of said body member.

2. A toggle operating mechanism for an electric Wiring device comprisinga housing, an elongated spring, means in said housing for supportingsaid spring at two spaced points, a body member pivotally supported bysaid housing on an axis transversely disposed with relation to saidspring between said spaced points, said body member having a generallyU-shaped surface with the arms of said surface extending away from theapex thereof at a curvature having a radius such that a portion of saidarms located adjacent the apex are closer to the pivot point of the bodymember than the apex and the extremities of said arms and spaced afurther distance from said pivot point than said apex, respectively,said body mem ber being located with respect to said spring so that oneof said arms is initially in longitudinal engagement with said spring soas to cause said spring to be initially stressed, said body member beingpivotally movable so that said apex moves along said spring such thatsaid spring engages the other of said arms in the same manner and suchthat each of said arms progressively engages said spring to provideresilient stopping action for said body member.

3. A toggle operating mechanism for an electric wiring device comprisinga housing, an elongated spring, means in said housing for supportingsaid spring at two spaced points, a body member pivotally supported bysaid housing on an axis transversely disposed with relation to saidspring between said spaced points, said body member having a groovetherein comprising two longitudinally aligned convex inclined portionsjoined at a common apex, said groove being of a contour so as toslidably receive said spring, said body member being located withrespect to said spring so that one inclined portion of said groove isinitially in substantially longitudinal engagement with said spring soas to cause said spring to be initially stressed, said body member beingpivotally movable so that said apex moves along said spring and saidspring engages the other portion of said groove in the same manner, eachof said convex portions being formed to recede upwardly and away fromsaid apex with said convexity being an an effective radius longer thanthe distance of each point on said groove from the pivot point of saidbody member and with the center of said convexity being spaced from aline passing through said apex and said pivot point so that each of saidconvex portions progressively engages said spring to provide resilientstopping action for said body member.

4. A toggle operating mechanism for an electric wiring device comprisinga housing, an elongated wire-like spring supported at each of its endsby said housing, a body member pivotally supported by said housing on anaxis approximately transversely disposed with relation to the center ofsaid spring, said elongated body member having a groove thereincomprising two generally inclined portions joined at a common apex, saidgroove being of a contour so as to slidably receive said spring, saidbody member being located with respect to said spring so that oneinclined portion of said groove is initially in engagement with saidspring so as to cause said spring to be initially stressed, said bodymember being pivotally movable so that said apex moves along said springwhereby said spring engages the other portion of said groove in the samemanner, said apex having a contour so that said body member is unstableat its dead center position, and each of said inclined portions beingslightly curved along its generally longitudinal dimension to recedefrom said apex on a radius longer than the distance of each point onsaid inclined portion from the pivot point of said body member so thateach of said inclined portions progressively engages said spring toprovide resilient stopping action for said body member.

References Cited by the Examiner UNITED STATES PATENTS 3,089,937 5/63Von Hoorn et a1 200-152 BERNARD A. GILHEANY, Primary Examiner.

ROBERT K. SCHAEFER, Examiner.

1. AN ELECTRIC SWITCH COMPRISING, A RECTANGULAR CUPSHAPED INSULATINGHOUSING, AN ELONGATED SPRING LOCATED WITHIN SAID HOUSING AND EXTENDINGTRANSVERSELY BETWEEN ONE PAIR OF OPPOSED WALLS OF SAID HOUSING, MEANS INEACH OF SAID ONE PAIR OF OPPOSED WALLS FOR SUPPORTING OPPOSED ENDS OFSAID SPRING, A BODY MEMBER PIVOTALLY SUPPORTED ABOVE SAID SPRING BY THEOTHER PAIR OF OPPOSED WALLS OF SAID HOUSING, SAID BODY MEMBER INCLUDINGA LOWER SURFACE HAVING A CENTRAL APEX WITH AN INCLINED SURFACE AT EACHSIDE OF SAID APEX, SAID SPRING AND SAID BODY MEMBER BEING LOCATED WITHRESPECT TO EACH OTHER IN SAID HOUSING SO THAT WHEN ONE OF SAID INCLINEDSURFACES ENGAGES SAID SPRING SAID SPRING IS STRESSED, SAID BODY MEMBERBEING PIVOTALLY MOVABLE SO THAT SAID APEX FURTHER STRESSES SAID SPRINGAND CAUSES SAID SPRING TO ENGAGE THE OTHER OF SAID INCLINED SURFACES INTHE SAME MANNER, EACH OF SAID INCLINED SURFACES BEING FORMED TO CURVEUPWARDLY AWAY FROM SAID APEX IN A TRANVERSE DIRECTION WITH RESPECTTHERETO ON A RADIUS LONGER THAN THE DISTANCE OF EACH POINT ON SAID LOWERSURFACE FROM THE PIVOT POINT OF SAID BODY MEMBER SO THAT PROGRESSIVEENGAGEMENT OF EACH OF SAID INCLINED SURFACES WITH SAID SPRING PROVIDESRESILIENT STOPPING ACTION FOR SAID BODY MEMBER, SEPARABLE ELECTRICALCONTACT MEANS LOCATED WITHIN SAID HOUSING AND MEANS ON SAID BODY MEMBERFOR MOVING SAID CONTACTS INTO AND OUT OF ELECTRICAL ENGAGEMENT INRESPONSE TO SAID PIVOTAL MOVEMENT OF SAID BODY MEMBER.